This invention is directed to electronic couplers and, more particularly, to couplers for coupling signals to communication wire pairs, such as the tip and ring leads of telephone communication systems.
In the past, signals such as tone, voice, data and the like have been coupled to the wire pairs of communication systems, such as the tip and ring leads of telephone communication systems, via a transformer. For example, when a telephone goes off in order to answer an incoming call, an indication of the off-hook status of the telephone is created by coupling an answer tone to the tip and ring leads. In the past, answer tone coupling has usually been accomplished via a coupling transformer. Similarly, other sources of information (e.g. speech, data and the like) have been coupled to the telephone tip and ring leads via a transformer. While transformers have found widespread use as signal couplers, they have certain disadvantages. For example, they often unduly load the telephone line. In addition, signal coupling transformers used in communication systems are generally larger and more expensive than desirable.
Therefore, it is an object of this invention to provide a new and improved signal coupler.
It is a further object of this invention to provide a signal coupler suitable for coupling communication signals, such as tone signals, voice signals, data signals and the like to a pair of wires of a communication system.
It is another object of this invention to provide a signal coupler suitable for coupling communication signals to a pair of communication wires without unduly loading the wires.
It is yet another object of this invention to provide a relatively small and inexpensive coupler for coupling signals to the wires of a communication system.